The present invention relates to a probe mechanism constituted by a tip member comprising a needle-like member brought into contact with a sample, and a pick up mechanism having a handling function of separating, picking up, storing or the like of a small sample, particularly a pick up mechanism highly convenient for cutting out a defect portion of a sample of a transmission electron microscope (TEM) or a semiconductor device which are attached to an analyzing apparatus of a focusing ion beam (FIB) apparatus or a scanning probe microscope (SPM).
There is carried out an operation of bringing a probe into contact with a small sample while observing the sample by a scanning electron microscope (SEM), a scanning ion microscope (SIM), or a scanning probe microscope (SPM) and inspecting a physical property of an electric property or the like thereof. Further, there is carried out an operation of cutting out and picking up a portion of a semiconductor wafer or the like to fix to a sample base or the like in picking up a TEM sample or cutting out a failed defect portion thereof. The operation is constituted by a series of operation of making a needle-like probe approach a specific portion of a sample by operating a manipulator, bringing a probe tip portion into contact therewith and thereafter fixedly attaching the probe tip portion thereto by deposition (CVD) by FIB, further cutting to separate a sample piece from a sample main body by FIB etching, thereafter, carrying a sample piece to a predetermined position at which a sample base or the like is present to fix by operating the manipulator, and subjecting the tip portion of the probe fixedly attached with the sample piece previously by CVD to FIB etching to cut to separate the sample piece while observing in a chamber of an FIB apparatus or the like.
Patent Reference 1 discloses a technology of separating a sample piece including a region to be observed from a sample board by an ion beam sputtering method, picking up the sample piece from the sample board by using a beam member comprising a rod-like member for holding the sample piece by a force by elastically deforming a portion thereof for pressing to hold the sample and drawing to separate the sample, having a shape of a tip slenderer than a root thereof and dividing the tip portion for holding the sample piece provided by the shape, moving the sample piece to a mounting base for mounting the sample piece and separating the beam member and the sample piece to store the sample piece with an object of providing an apparatus and a method of separating, picking up and storing the small sample piece firmly and stably without contaminating the small sample piece and a peripheral region thereof. The invention adopts a mode of grabbing the sample piece in a tweezers mode by pinching the sample piece by a divided portion to press and therefore, although it is not necessary to fixedly attach the probe and the sample piece by CVD to thereby shorten an operation time period in comparison with the background art, a considerable skill is needed in the operation of pinching the sample piece by operating a manipulator while observing the sample piece by the microscope. Further, depending on a size or a shape of the sample, a size and a shape of the divided portion needs to be changed and the sample piece may be damaged by exerting an unreasonable force in pinching the sample piece.
Further, Patent Reference 2 discloses a pair of microtweezers in which as shown by FIG. 5, bimorph type piezoelectric elements 102, 403 are arranged in a direction of elongating and contracting a laminated type piezoelectric element 101, a correction amount 112 is generated by strain gage elements 103 pasted on both faces of the bimorph type piezoelectric element and a correcting circuit 105, and by elongating and contracting the laminated type piezoelectric elements, loci of moving tips of probes 104, 404 are linearly displaced with an object of providing a probe moving apparatus, a microtweezers apparatus having excellent operability applicable also to fine operation by automatically correcting a deviation in a circumferential direction centering on a fulcrum of the bimorph type piezoelectric element produced by bending the bimorph piezoelectric element. The microtweezers pick up a small body of a micrometer level by utilizing a fact that an interval between the tips of the small probes is narrowed by applying a voltage to both or one of the bimorph type piezoelectric elements. By the constitution, the interval between the tips of the small probes 104, 404 can be controlled without positional shift and therefore, there is achieved an effect of capable of accurately and easily picking up a small body. Although according to the method, it is not necessary to fixedly attach the probe and the sample piece by CVD, not only the operational time period is shortened in comparison with the background art but also the grabbing operation is simple since the tweezers drive mechanism is provided, further, the sample piece is not damaged since the unreasonable force is not exerted thereto, the piezoelectric element is used as the drive source and therefore, it is necessary to connect a high voltage power source in driving the microtweezers, which is not preferable in handling a semiconductor sample or a living body sample. Further, a state of bringing the sample and the probe into contact with each other is obliged to confirm by microscope observation.
A technology of sensing contact between the probe and the sample is disclosed in Patent Reference 3 or Patent Reference 4. The invention of Patent Reference 3 is a technology of improving Patent Reference 2, it is an object thereof to provide inexpensive contact sensing means capable of sensing the contact of the sample and the probe regardless of a kind of the sample, and a probe comprising a needle-like conductive material having a tip in an acute angle shape is fixedly attached to a free end of a warp sensing beam having a piezoelectric resistance layer a resistance value of which is changed in accordance with a deformation of its own. Although contact between the sample and the probe can be sensed by adopting such a constitution, the constitution poses a problem that the sensing is limited in a direction of laminating piezoelectric elements. Further, it is an object of the invention of Patent Reference 4 to provide a probe apparatus capable of detecting that a small sample is completely cut off when a small sample is cut off from a sample of a wafer or the like to pick up by a probe, and it is detected that the small sample is completely cut off by previously applying a probe voltage from a probe control portion to the probe and detecting a change in the probe voltage immediately after cutting off the small sample from the sample by FIB. According to the contact sensing method, it is necessary to make a current flow in the sample and therefore, the method is based on a condition that the sample is conductive and the method is not applicable to a sample damaged, or destructed or the like by conducting electricity.
[Patent Reference 1] JP-A-2002-333387 “Beam member and sample machining apparatus and sample pick up method using beam member” Publication date; Heisei-14-11-22 (Nov. 22, 2002)
[Patent Reference 2] JP-A-2000-2630 “Probe moving apparatus and sample fabricating apparatus using the same” Publication date; Heisei-12-1-7 (Jan. 7, 2000)
[Patent Reference 3] JP-A-2002-33366 “Probe unit and sample operating apparatus using the same” Publication date; Heisei-14-1-31 (Jan. 31, 2002)
[Patent Reference 4] JP-A-2001-83055 “Probe apparatus” Publication date; Heisei-13-3-30 (Mar. 30, 2001)
A problem to be resolved by the invention resides in providing a probe mechanism or a small sample pick up mechanism of analyzing apparatus overcoming the above-described drawbacks of the mechanism of the background art, that is, providing a mechanism having a function of sensing contact of a sample and a probe without damaging the sample in approaching the sample, enabling to handle swiftly and firmly a small sample as a pick up mechanism and structurally simple without selecting a material of the sample.